In a typical communications network, also referred to as e.g. a wireless communications network, a wireless communications system, a communications network, a communications system or a wireless network, a wireless device communicates via a Radio Access Network (RAN) to one or more Core Networks (CNs).
The wireless device may be a device by which a subscriber may access services offered by an operator's network and services outside operator's network to which the operator's radio access network and core network provide access, e.g. access to the Internet. The wireless device may be any device, mobile or stationary, enabled to communicate over a radio channel in the wireless network, for instance but not limited to e.g. user equipment, mobile phone, smart phone, sensors, meters, vehicles, household appliances, medical appliances, media players, cameras, Machine to Machine (M2M) device or any type of consumer electronic, for instance but not limited to television, radio, lighting arrangements, tablet computer, laptop or Personal Computer (PC). The wireless device may be portable, pocket storable, hand held, computer comprised, or vehicle mounted devices, enabled to communicate voice and/or data, via the radio access network, with another entity, such as another wireless device or a server.
The wireless device is enabled to communicate wirelessly in the wireless network. The communication may be performed e.g. between two wireless devices, between a wireless device and a regular telephone and/or between the wireless device and a server via the radio access network and possibly one or more core networks and possibly the internet.
The wireless network covers a geographical area which is divided into cell areas. Each cell area is served by a base station. The base station may be referred to as e.g. evolved Node B (eNB), eNodeB, NodeB, B node, Base Transceiver Station (BTS), Radio Base Station (RBS), depending on the technology and terminology used. The base station communicates over the air interface with the wireless device(s) within range of the base station.
The wireless network further comprises network nodes such as Serving GateWay (SGW), Packet data network GateWay (PGW), Mobility Management Entity (MME), Home Subscriber Server (HSS) etc.
Today wireless networks suffer from an increasing signaling load. This is mainly due to wireless devices frequently going online to download updates etc. for applications and features.
To save radio power consumption, e.g. battery consumption, the wireless device may quickly disable its radio whenever possible. This may be done by setting the wireless device in power saving modes such as idle mode or connected mode. A mode may also be referred to as a state. When the wireless device is not in the idle mode or the connected mode, it may be in active mode and it is actively connected to the base station, i.e. it is not in any power saving mode. The active mode may also be referred to as awake mode. The connected mode may also be referred to as a discontinuous reception mode, in which the wireless device performs discontinuous reception when saving radio power consumption. The connected mode may be DRX in connected mode if the wireless network is a Long Term Evolution (LTE) network or URA-PCH if the wireless network is a 3G network, e.g. Universal Mobile Telecommunications System (UMTS). DRX is short for discontinuous reception. URA is short for Universal terrestrial radio access network (UTRAN) Registration Area and PCH is short for Paging CHannel.
If the need to save radio power consumption is signalled as the idle mode to the wireless device, it will lead to that all resources related to the wireless device are being released in the base station. Next time the wireless device comes online, i.e. enters active mode, all these resources have to be recreated. This causes signaling load in the wireless network.
DRX and URA-PCH may be used both in connected mode or idle mode. However, the embodiments herein relate to DRX in connected mode and URA-PCH in connected mode. If the need to save radio power consumption is signalled as the DRX in connected mode or URA-PCH in connected mode to the wireless device, the wireless device effectively stays connected with the base station, while the radio in the wireless device is turned off. This will not release resources in the base station, and signaling is kept to a minimum. DRX in connected mode and URA-PCH in connected mode may however cause more signaling, since handover must be done for all movements around the wireless network. Handover may be described as transfer of ongoing data session for a wireless device from one base station to another base station. DRX in connected mode and URA-PCH in connected mode is a process of turning off the radio receiver in the wireless device when it does not expect to receive incoming data. When the wireless device is in DRX in connected mode and URA-PCH in connected mode, its radio is periodically and momentarily switched on, to check for any pending downloads from the wireless network. Connected mode may also be referred to as sleep mode. This reduces the radio power consumption which extends the battery life of the wireless device. DRX in connected mode should not be mixed up with DRX in idle mode in which the wireless device may be set into after a time of air interface inactivity.